AutoCad Drawings Small Edits & Simple Redesign

I am looking to get 2 - 3 technical drawings updated with new dimensions. files are in a .dxf file (I believe this is autocad extension). The mechanical parts are drawn in 2D with dimensions along with a 3D rendering of the product. Along with the small edits to the existing files, I would also like to redesign a product to make it more compact (reduce material cost and improve design). I occasionally have drawings to get updated so this could turn into a long term relationship. Along with your quote, please include some samples or link to a website showing some work samples. The bid values will be generic as I do not want to post our proprietary drawings but you will have an opportunity to re-quote with the full product details and scope of work. I will probably pick out 3 - 4 freelancers with good examples and good feedback for an official quotation. If you have any questions, please do not hesitate to ask.